In an attempt to uncover the truth behind this tragedy, Garbus speaks with all of the willing and available investigators, family members (including Schuler's husband) and witnesses present at the crash site. While her rigorous questioning reveals some new insights, like Schuler's troubled childhood and a possible medical emergency that may have precipitated her actions, ultimately There's Something Wrong With Aunt Diane can't provide any definitive answers for what happened that day on the Taconic. But it's compelling to watch Garbus skillfully assemble the pieces of this puzzle. Stay tuned for the final three docs in the network's summer series, including Koran By Heart (August 1), Superheroes (August 8) and Gloria: In Her Own Words (August 15), a portrait of groundbreaking feminist Gloria Steinem.

There's Something Wrong with Aunt Diane airs tonight at 9 PM on HBO opposite new episodes of The Bachelorette (ABC) and Switched at Birth (ABC Family).